NMR studies of natural and synthetic DNA fibers in the B form showed that significant variations exist in the phosphodiester backbone. NMR studies of molecules dissolved in liquid crystal solvents in the nematic phase have provided accurate and detailed information about intramolecular geometry in phenazine, N-methylimidazole and phenylisilane. NMR parameters of 57Fe have been measured in order to characterize this infrequently studied nucleus and facilitate its use as a structural probe. The chemical shift range to be expected in various compounds has been defined, and the mechanisms of spin-lattice relaxation of a ferrocene derivative have been established.